I keep getting addresses showing up in my bounce reports as non-existent. I know these are valid addresses, as I communicate with the address owners all the time at the very same address. I have inspected each one and they are entered correctly.
All I can tell you is that it does happen. We get mail bounced as non-existent and we communicate with these people in our regular mail system without problem.
They must have their servers report blocked items as non-existent, perhaps hoping for a greater chance for removal from the list.
So, to keep the non existent addresses on our lists, or not?
Same problem here, and my problem is that over 50% of my contacts have the same email provider (our local school district). I was given a list of IP addresses to put in our system, but that didn't help. I am now trying to find another company like this since having over 50% of my emails get bounced as non-existent address (including MINE!) makes having this whole thing pointless and a waste of money.
Oddly enough, we can send to one user at a facility but not another. The problem seems random on specific domains but occurs on the same email address consistently. Do you think it has something to do with CaSe SeNsITivity?